The marriages were performed Saturday before a federal appeals court suspended a decision that overturned the state's ban on gay marriage.

Snyder's announcement Wednesday closes the door to certain benefits granted to Michigan married couples. The move comes after a day after an appeals court indefinitely stopped any additional same-sex marriages.

Snyder says the marriages were legal at the time but the stay means the ban now is back in effect.

The court is reviewing a decision by Detroit federal Judge Bernard Friedman, who struck down a 2004 constitutional amendment that says marriage is between a man and a woman.

It will take months for the appeals court to affirm or reject Friedman's opinion.